Estudo químico-biológico das folhas de Bocageopsis multiflora (Mart.) R.E.FR, Duguetia quitarensis Benth, Fusaea longifolia (Aubl.) Saff e Guatteria punctata (Aubl.) R. A. Howard (Annonaceae)

• Ano de defesa: 2022
• Autor(a) principal: Bay, Márcia
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Mato Grosso; Brasil; Instituto de Biociências (IB); UFMT CUC - Cuiabá; Programa de Pós-Graduação em Biodiversidade e Biotecnologia - Rede BIONORTE – PPG-BIONORTE
• Palavras-chave em Português: Óleo essencial; Extrato bruto; Alcalóides; HRQTOF-ESI/MS; CNPQ::OUTROS::CIENCIAS; Essential oil; Crude extract; Alkaloids
• Link de acesso: http://ri.ufmt.br/handle/1/6119

Annonaceae are frequently found in tropical rainforests, and present a wide variety of secondary metabolites. Therefore, in order to contribute with the scientific knowledge of this family, we studied the species Bocageopsis multiflora (BG), Duguetia quitarensis (DQ), Fusaea longifolia (FL) and Guatteria punctata (GP), commonly found in the state of Rondônia. Species of the family Annonaceae are known by their ethnobotanical studies, presenting a wide variety of pharmacological activities. Within this context, these species were chosen for Chemical and biological investigations. The leaves were collected, dried at room temperature, crushed, and their essential oils (EO’s) were extracted with a modified Clevenger apparatus. GC-ME analysis lead to the identification of 23 (BG), 20 (DQ), 21 (FL) and 23 (GP) constituents, observing the predominance of sesquiterpenes and their oxygen derivatives, where (E)-caryophyllene was present in all investigated species at a higher concentration. In the biological experiments carried out with the EO’s, we observed in vitro activity against Trypanosoma cruzi, for which all extracts were active. Among the investigated extracts, the EO from G. punctata stands out (IC50 = 0.029 ± 0.014 µg/mL), being 34 times more potent than benznidazole, used as reference drug. Antibacterial acitivity was also observed, with the EO from BG being the most active compound against Gram-negative and Gram-positive bacteria, and the EO from FL being active agaisnt Gram-negative bacteria. For the methanol and ethanol extracts from the leaves, preliminary phytochemical screening detected the presence of phenols and tannins for BG, FL, GP, flavonoids for DQ, alkaloids for DQ and GP, and sterols and triterpenes for FL and GP. When determining the total phenol content, BM also presented the best EC50 value for the ethanolic (11.1 µg/mL ±0.24) and methanolic (4.2 µg/mL ±0.75) crude extracts. Through dereplication by direct infusion (ESI-IT-MS), it was possible to identify four aporphinic alkaloids in the methanol extract from DQ (MEDq), while for GP(MEGp), 20 alkaloids were identified through mass spectroscopy coupled to ultra performance liquid chromatography (UHPLC-QTOF-MS): nine from the benzylisoquinoline class, seven aporphine alkaloids, one oxoaporphine alkaloid, one IV simple isoquinoline alkaloid, and two of other classes: one pyrrolidine alkaloid and the other belonging to the azaanthracene class. The results obtained for the fixed constituents of DQ and GP contributed with the classification of these species within the Annonaceae family, once the isoquinoline-derived alkaloids are presente in most genera belonging to this family. Crude extracts at concentrations of 1, 3, 9, 27, 81 and 243 µg.mL-1 showed considerable antioxidant activity in the assays performed by the DPPH method, with BM showing the best activity. The antibacterial activity of ethanolic and methanolic crude extracts when evaluated by the Agar diffusion method - well technique, showed that all samples tested were inactive against the microorganisms tested: enterohemorrhagic Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica subsp. enterica Serovar Typhimurium, Staphylococcus aureus, Staphylococcus sumulans.